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Sluggish multiphase reaction kinetics and severe shuttle effect of lithium polysulfides (LiPSs) are two major challenges facing lithium-sulfur (Li-S) batteries, which largely prevent them from becoming a reality. Herein, a shell with catalytic function for sulfur cathode is in situ constructed through an ingenious electrochemical oxidative polymerization strategy by introducing hexafluorocyclotriphosphazene (HFPN) as additives, which suppresses the shuttle effect and promotes efficient sulfur conversion. The shell with abundant heteroatoms effectively confines polysulfides to the cathode matrix by chemically interacting with them to eliminate capacity degradation. Moreover, the shell exhibits high catalytic activities, which turns Li

In 40Ar/39Ar dating, 39ArK generated is dependent on irradiation conditions, and the accumulation fast neutron fluence is a critical parameter for 40Ar/39Ar dating. With technological advancement, especially in the ultra-low background and multicollector technology, the boundary conditions to choose irradiation conditions have been greatly improved. Based on the detected and processed signal, the maximum boundary condition of 40Ar*/39Ar can be up to 5750, meaning that very low 39Ar signals can yield considerable analytical accuracy. In this study, one biotite sample (ZBH-25) was irradiated for 4 hours to assess the modified irradiation conditions, and the high 40Ar*/39Ar ratio up to 4100 could yield ∼1% analytical uncertainty. This reveals that the new boundary condition is useful to choose fast neutron fluence, especially for very old or low K/Ca ratio samples.

s Background Recently, the effects of erector spinae plane block on postoperative pain have become increasingly controversial. This meta-analysis compared the effects of ESP block versus placebo on postoperative analgesia and side effects to determine whether the new technique is a reliable alternative for pain management. Methods PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang Database were searched for clinical studies investigating the analgesic effect of ESP block versus placebo. The primary outcomes included the visual analogue scale (VAS) at rest and during movement, as well as the postoperative morphine consumption in 24 h, and the secondary outcome was the rate of postoperative nausea and vomiting (PONV). The choice of using the fixed or random-effects model depended on whether the heterogeneity tested by I2 statistic was more than 50%. Seeking sources of heterogeneity and exploring the effect of clinical details on the final result were performed by subgroup analysis. Additionally, the test for stability of the pooled result was realized by sensitivity analysis. Finally, we evaluated the quality of the evidence for the outcomes. STATA 13.0 software was selected as the main analysis software in the meta-analysis. Results Eighteen randomized controlled trials (RCTs) comprising 1041 patients were reviewed. This meta-analysis showed that ESP block could significantly reduce patients' pain scores at 1 h, 6 h, 12 h, and 24 h after surgery at rest or during movement; 24-h postoperative morphine consumption; and the incidence of PONV. Conclusions ESP block as a novel technique exhibited superior postoperative analgesic effects, reducing the postoperative complications in spinal, thoracic, and abdominal surgeries during the early postoperative period. However, as a new nerve block technique, numerous large-sized RCTs are needed for further research.

Thermal cycling tests (TCT) have been widely used for performance demonstration and reliability validation of the spacecraft electronics. The integrated tailoring model can provide customized testing conditions of TCT for different spacecraft electronics, which is different with the traditional unified tailoring model in MIL-STD-1540. Considering the influence of welding material, defect degrees and test levels, experimental verification had been done on solder samples. The evaluation indicators including test cost, simulation bias and simulation accuracy have been defined and compared between two different tailoring methods. The results show that for Sn/Pb solder samples, the testing effects of the two tailoring methods are the same. But for other materials solder samples, the integrated method can be used to achieve better environmental stress screening with lower cost than the traditional method. Such as the SAC solder, the simulation accuracy is increased by 0–10%, and the testing cost is decreased by 0–7%.

The historical failure data of launched spacecraft are very useful to improve the designing and manufacturing of spacecraft, optimize ground tests and reduce the flight risks of spacecraft. In 2010, the study of spacecraft failure data was initiated in China. Since 2017, 2593 on-orbit failure data and 1298 ground failure data for 120 spacecraft launched from 2000 to 2017 have been identified and collected, including navigation satellites, communication satellites, remote sensing satellites, deep space exploration missions and manned spacecraft. In this paper, the development of China's aerospace manufacturing industry in the last decade is objectively evaluated by analysis of these failures, based on the most comprehensive available statistics of Chinese spacecraft. Detailed failure causes, failure impacts, affected subsystems, higher-risk components of spacecraft are analyzed. The failures exposure rate of ground tests and the number of early flight failures are also numerically estimated. Finally, the statistical evidence is provided in this paper to support the conclusion: reducing design errors, improving advanced research, adequate redundancy, effective space environmental protection measures, and adequate ground testing are the key to improve spacecraft quality.

A new species of the genus Cenocorixa Hungerford (Hemiptera, Heteroptera, Corixidae) is described from China. Cenocorixa yuanjiangensissp. nov. is reported from Yunnan Province. An updated key to the Chinese species of Cenocorixa is presented.

Chemotherapy resistance is still a key hurdle in current hepatocellular carcinoma (HCC) treatment. Therefore, clarifying the molecular mechanisms contributing to this acquired resistance is urgent for the effective treatment of liver cancer. In this research, we observed that lncRNA FAM225A expression is dramatically up-regulated not only in HCC tissues and cell lines but also in sorafenib-resistant HepG2/SOR cells. Moreover, FAM225A knockdown significantly weakened HepG2/SOR cells resistance to sorafenib treatment by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Similar results were obtained from the tumor xenograft model in mice. Further mechanistic researches revealed that the direct interaction between FAM225A and miR-130a-5p, while miR-130a-5p negatively modulated Cyclin G1 (CCNG1) expression by targeting 3′UTR of CCNG1. MiR-130a-5p inhibition or CCNG1 overexpression could partially offset FAM225A knockdown-induced increased viability of HepG2/SOR cells in response to sorafenib challenge. Collectively, our findings provide evidence that FAM225A/miR-130a-5p/CCNG1 interaction network regulates the resistance of HCC cells to sorafenib treatment and could supply a possible strategy for restoring sorafenib sensitivity in HCC therapy.

Meiotic recombination caused by meiotic double-strand DNA breaks. In some regions the frequency of DNA recombination is relatively higher, while in other regions the frequency is lower: the former is usually called "recombination hotspot", while the latter the "recombination coldspot". Information of the hot and cold spots may provide important clues for understanding the mechanism of genome revolution. Therefore, it is important to accurately predict these spots. In this study, we rebuilt the benchmark dataset by unifying its samples with a same length (131 bp). Based on such a foundation and using SVM (Support Vector Machine) classifier, a new predictor called "iRSpot-Pse6NC" was developed by incorporating the key hexamer features into the general PseKNC (Pseudo K-tuple Nucleotide Composition) via the binomial distribution approach. It has been observed via rigorous cross-validations that the proposed predictor is superior to its counterparts in overall accuracy, stability, sensitivity and specificity. For the convenience of most experimental scientists, the web-server for iRSpot-Pse6NC has been established at http://lin-group.cn/server/iRSpot-Pse6NC, by which users can easily obtain their desired result without the need to go through the detailed mathematical equations involved.

The three species ofNerthraSay, 1832 (Hemiptera: Heteroptera: Gelastocoridae) occurring in China are reviewed. Dorsal habitus photographs of the two species,Nerthraasiatica(Horváth, 1892) andNerthraindica(Atkinson, 1889), are provided, accompanied by illustrations of male genitalic structures and female ventral aspect of posterior abdominal segments. The male ofNerthraasiaticais recorded and reviewed for the first time.

Three La-doped CeO2-ZrO2-Al2O3 (CZA) composite oxide samples, namely, CZA-I, CZA-II and CZA-III, were prepared following a co-precipitation method in the presence of La2O3, La(NO3)3·6H2O and H[La(EDTA)]·16H2O precursors, respectively. When the precursor samples are sintered at 1000 °C, the as-prepared composite oxides mainly exhibit the CeO2-ZrO2 cubic fluorite phase, while the γ-Al2O3 and δ-Al2O3 phases appear when the precursor samples are subjected to sintering at 1100 and 1200 °C. CZA-III exhibits improved redox properties after high-temperature treatment compared with CZA-I and CZA-II. CZA-III presents the largest surface area of 97.46 m2/g among the three CZAs when the CZA-III precursor sample is sintered at 1000 °C. Furthermore, the corresponding oxygen storage capacity (OSC) is the largest with value of 400.27 μmol/g when CZA-III precursor sample is sintered at 1000 °C. Additionally, CZA-III exhibits the best thermal stability and the highest reduction temperature. However, by increasing the sintering temperature to 1200 °C, there is a dramatic decline in the properties of surface area and OSC. And a decrease for CZA-III in surface area by 58.94% and a decrease of the OSC value by 74.56% are observed.

In this paper, the exponential stability in mean square of the exponential Euler method for semi-linear stochastic differential equation with piecewise continuous arguments is obtained. Firstly, the exponential Euler scheme of the equation is given. Secondly, under Lipschitz condition, sufficient conditions of exponential stability to the exact solution are achieved in mean square. Furthermore, it is proved that exponential Euler method preserves exponential stability of the exact solution without any restriction on the step-size. Finally, an example is provided to illustrate our theories.

Molybdenum oxide nanomaterials have recently attracted widespread attention for their unique optical properties and catalytic performance. However, until now, there is little literature on the application of photoluminescent molybdenum oxide nanomaterials in biological and pharmaceutical sensing. Herein, photoluminescent molybdenum oxide quantum dots (MoOx QDs) were synthesized via a facile method, and then, the synthesized MoOx QDs were further applied as a new type of photoluminescent probe to design a new off–on sensor for captopril (Cap) determination on the basis of the fact that the quenched photoluminescence of MoOx QDs by Cu2+ was restored with Cap through specific interaction between the thiol group of Cap and Cu2+. Under optimal conditions, the restored photoluminescence intensity showed a good linear relationship with the content of Cap, ranging from 1.0 to 150.0 μM, with a limit of detection of 0.51 μM (3σ/k). Additionally, the content of Cap in pharmaceutical samples was successfully detected with the newly developed off–on sensor, and the recoveries were 99.4–101.7%, which suggest that the present off–on sensor has a high accuracy.

Thermal tests of electronic units are critically important for the reliability validation and performance demonstration of spacecraft hardware. A tailoring equation like that provided by MIL-STD-1540s is necessary for the testing condition planning of these thermal tests, however, the tailoring equation provided by MIL-STD-1540s is mainly based on the fatigue data of solders. In this paper, a new test condition tailoring equation is proposed by introducing an integrated evaluating method for the fatigue acceleration exponent. The different thermo-mechanical fatigue mechanisms and different subsystem characteristics have been considered and discussed in the deducing of this new equation. The test precipitation efficiency (PE) of the new tailoring law has been analyzed and compared with that from the MIL-STD-1540 tailoring equations. The results are encouraging and reasonable.

Toll-like receptor 4 (TLR4) has received a lot of attention in studies on ischemia-reperfusion (I/R) injury. TLR4 is one of the target genes for microRNA-182-5p (miR-182-5p)-mediated regulation. In this study, we evaluated the role(s) of miR-182-5p transcriptional regulation in a hepatic I/R injury model in vivo and a lipopolysaccharide (LPS)-induced inflammatory reaction model in vitro.The effects of miR-182-5p expression on the transcription and translation of TLR4 and several proinflammatory cytokines in a LPS-induced macrophage model were studied in vitro. After miR-182-5p was exogenously administered, the transcriptional/translational profile of TLR4 and the proinflammatory cytokines were evaluated in an in vivo I/R injury model. This data were combined with alanine transaminase expression levels and histologic features in an effort to understand the role(s) of miR-182-5p in a liver I/R model.TLR4 mRNA and protein levels in LPS-induced macrophages were significantly decreased in the presence of miR-182-5p (P .01). In vivo TLR4 mRNA and protein levels as well as the induction of several proinflammatory cytokines, including tumor necrosis factor α and interleukin-6, were decreased in the presence of miR-182-5p. Hematoxylin and eosin staining showed that edema and necrosis in I/R modes were alleviated in the miR-182-5p-expressing group compared with control.miR-182-5p attenuates hepatic I/R by directly suppressing TLR4.

The thermal properties of raw wood (RW) biomass, corresponding pyrolytic wood (PW) biomass, and their blends with anthracite coal (AC) were evaluated under combustion conditions with a thermogravimetric analysis (TGA) method. The blending ratios of the biomass with AC ranging from 0 to 100 mass% were taken into consideration to investigate the thermal behavior and kinetics of these blends during their co-combustion. For blends with different ratios of the RW to AC and 100% AC (100 AC), two distinct mass loss peaks related to the release or combustion process of the volatiles and the combustion of the char were noted. The addition of a higher ratio of RW or PW into AC can improve the combustion process of the blends. The thermal behavior of the RW/AC or PW/AC blends could not be characterized by a simple linear correlation of their pure material thermal behavior. With the RW/PW addition ratios varying from 25 mass% to 80 mass%, the apparent activation energy of the blends gradually decreased from 48. 46 to 34. 93 kJ/mol and from 82. 74 to 37. 81 kJ/mol for the RW/AC and PW/AC blends, respectively, with high correlation coefficient (R2) values ranging from 0. 995 6 to 0. 9984.

The current cutting equipment and methods cannot meet the demand of offshore wind cut jacket. In order to solve this problem, we develop a new suit of offshore wind jacket intersecting line cutting equipment. In this paper, detailed structure and operating guide of the equipment have been presented. The characteristics and application range are also included. The new equipment is simple and practical.

The spacecraft with large flexible space structures may be subject to the thermally induced vibration (TIV) due to the rapidly changed solar heat flux when it enters and leaves the eclipse, which would lead to certain spacecraft failure. This paper reports a laboratory experiment that aims to study the impact of transient characteristics of heat flux on the ground experiment of TIV. In the experiments on the TIV of a slender thin-walled beam, two different methods of providing transient heat flux were considered, and the process of entering and leaving eclipse was simulated, respectively. The experimental results demonstrate that different transient characteristics of heat flux will have large impact on the TIV of the specimen, and the ideal theoretical estimation of thermal characteristic time has limitations in practical engineering. In addition, it is found that the traditional way of simulating solar heat flux by turning on/off infrared heat lamps is not suitable for the TIV ground experiment. Instead, a transient heat flux simulation method by moving the baffle is recommended.

In this paper, exponential stability in mean square of the exponential Euler method to linear stochastic differential equation with piecewise continuous arguments (LSEPCAs) is showed. We give the exponential stability in mean square of the exact solution to linear stochastic differential equation with piecewise continuous arguments by using interval with integral end-points method and definition of logarithmic norm. The exponential Euler method to linear stochastic differential equation with piecewise continuous arguments is proved to share the same stability for any step size by property of logarithmic norm. Finally, an example is provided to illustrate our theories.

Arma custos and A. chinensis have a very conspicuous difference in the shape of the pronotal humeral angle, but the genitalic morphological characters are ambiguous and difficult to recognize. The aim of this study was to analyze the taxonomic status of A. chinensis and A. custos based on morphological, molecular, and geographical evidence, and to determine whether DNA barcoding could be a useful additional tool for differentiating similar species. The results clearly demonstrate that A. custos and A. chinensis have not diverged into separate species. So, the following new synonym is proposed: Arma chinensis Fallou, 1881 = Arma custos (Fabricius, 1794) syn. nov.. The results also showed that DNA barcoding using the marker COI can resolve insect taxonomic problems.

Two new disesquiterpenoids (1 and 2) and 11 new (3–13) and 10 known (14–23) sesquiterpenoids were isolated from the whole plants of Artemisia freyniana. Their structures were elucidated by spectroscopic data analysis and comparison with published NMR data. The absolute configurations of the new isolates (1–13) were assigned based on single-crystal X-ray diffraction data and comparison of the experimental and calculated ECD data. The eremophilane derivatives 8 and 9 possess an unprecedented 2-isopropyl-3,7,7a-trimethyl-2,4,5,6,7,7a-hexahydro-1H-indene scaffold, and a putative biosynthetic pathway for these compounds is proposed. Compounds 4, 5, and 9 exhibited inhibitory effects against LPS-stimulated nitric oxide (NO) production in RAW 264.7 macrophage cells with IC50 values of 10.8, 12.6, and 11.7 μM, respectively.

Four types of piscidinol A derivatives were synthesized and evaluated their ability to inhibit HIV-1 protease to understand their structure-activity relationships. Of these tirucallane-type triterpene derivatives, an A-seco derivative (1b) moderately inhibited human immunodeficiency virus (HIV) protease (IC50 38.2 μM). The 2,2-dimethyl succinic acid (DMS) acylated tirucallane derivatives (4b, 6a, and 7b, 50 IC50 100 μM) were more inhibitory against HIV-1 PR than the others (PA, 2a, 4a, 4c-4d, 5a, 6b-6d, and 7a, IC50 100 μM). These findings indicated that the 2,3-seco-2,3-dioic acid (1b) and DMS-acylated tirucallane-type derivatives preferably inhibited HIV viral protease.